Hi @faskham,
I hope you are well today and thank you for your question.
Are you using any cache on your site?
If yes then please clear it and try temporary disabling it.
Please make sure you are using latest version of PHP on your server by referring the information provided in the following pages.
https://www.wikihow.com/Check-PHP-Version
http://php.net/supported-versions.php
This can be due to plugin conflict on your site so please try temporary deactivating all plugins except Unyson plugin and WpBakery page builder plugins and see whether everything works fine and then enable the plugins one by one to see which plugin is conflicting if any or use following plugin to check it.
https://wordpress.org/plugins/health-check/
Best regards,
Shufflehound team